Method for improving peat fuels and the like



Nov. 15, 1932. D w, B UN 1,887,671

METHOD FORVIMPROVING FEAT FUELS AND THE LIKE Filed Jan. 28, 1930 a F/'9./b

r j/l m Z Q z/zd WrnerBerZin Patented Nov. 15, 1932 UNITED STATES PATENIT'OFFI'CVE A a mm WERNER BERLIN, or nnsU a, swnnmr nn'rnon ron mnovrne PEAT rnnLs'nnn ran LIKE Application filed January 28, 1930, Serial No; 424,115, and in sweden lebruary B, 1928.

My present invention refers to a method for improving or transforming peat orother inferior fuels into similar products of Y a superior quality by removal of moisture from such substances as wet-carbonized peat,

or peat otherwise pre-treated, sawdust, wood splintersior waste wood in general, dried grasses and the like. At the separation of a liquid from a finely disintegrated material, the difficulty lies in the obtaining of a sufficient degree of dryness, as a finely disintegratedmaterial possesses a greater capillary power actingifor retention of the liquid than a material consisting'of coarser grains.

In order to perform an'efiicient drying actionby mechanicalinfluence, it is required that the drying is performed according to principles making it possible to subject'the liquid constituent to a maximum of separative power both when removing the main part thereof and when removing the final rests. e I

My present invention involves a solution to this problem and consists mainly therein that the substance to be dried or dewatered,

which substance is pro-treated in a manner known per se, for instance by wet-carbon'ization, during a first stage of treatment, for

removing the main amount of liquid, is

thrown out from the liquid, whereafter the liquid,-during a second stage of treatment for removing the small rest thereof, is thrown away from the solid substance.

In practice these principles are carried into eflect in such a manner that a liquid containing substance, or a solid substance sludged in a liquid, by means of centrifugation is at first separated from the main amount of liquid by treatment in a centrifugal machine,

the bowl'or drum of which is provided with unpenetrable walls, so that the solid substance, due to the centrifugal action arising, is

thrown through theliquid and settles against the impenetrable walls of the drum, :the liquid being forced towards thecentre of the drum and removed therefrom, whereafter the product is again centrifugated when resting on perforated or generally liquid penetrable walls, so that the centrifugal action then aris 0 ingforcesthe rest of the liquid-through the solid product and further through ,the penetrable walls of the drum, In this manner the ideal condition'is obtained thatthe power required for -separation of the constituents is applied just at that-point where it'is, able to act in the mos favourable and effective manner, i. e. directly within the material.-

In the first stage-of treatment of the material in the centrifugal machine, i may b '60 advantageous to sub-divide theproduet set- .t led against the wall of the drum into different layers or strata, and such stepca-n be performed either by means of insertion of perforated division wallsorj, atthe discharge I of the product from the machine, to cllt' rout thesame in differentlayers. The reason here to is I that when separating certain, substances, the layer settled nearest to the Wall of the drum may have such very lowcontent vof moisture that it need not be subjected .to the second stage of treatment. Although applicable to materials of differ- .ent kinds, the invention is mainly intended for separation of wet-carbonized peat from water mixed therewith, and-this, object is obtained in such a way that the peat is at first separated from the main bulk ,of water by treatment in a centrifugalmachine the drum: of which has unpenetrable-walls, so I that the peat mass is collected .on-the inner; face of the wall of the drum, the water being forced inwardly therein towards the centre, whereafter the peat is again subjected to centrifugation in anotherlmachine provided T ith perforated, porous or otherwise liquid penetr'able walls, so that the water is thrown out therethrough. 7

In a specific embodiment of invention, adapted for making the process automatic in the greatest possible degree, the peat is at first separated from the main bulk of I water in the manner described above, whereafter the unpenetrable walls are madeliquid penetrable, by forming suitable openings therein, and the, peat in the same machine is subjected to another centrifugationuat which the'rest of the water isrthrown away through said openings.

'In another embodiment of invention,

adapted for simplifying the process and for making it possible to use one single centrifugal machine throughout, the peat is at first separated from the main bulk of water in the manner described whereby certain portions of the dry substance is settled within cavities provided in the wall of the drum,

whereafter the remaining water at a later stage of separation is forced out through the peat substance at hand in these cavities.

In order to increase the working capacity at the separation,-it maybe suitable in cer-- tain cases /depending on uncommon of the materials to be separated/ to permit the.

finestsludgy particles at the first stage of separation to depart from the separator together with the liquid, so as either to be admixed again with the raw material fed in, or permitted to settle out from the liquid in order thereafter in amore concentrated condition to be introduced into the separator again. a 1 V The annexed diagrammatical drawing is intended to show some different embodiments Fig. 2 shows a centrifugal separator; adapted to be used as single machine forthe complete process and provided with a double walled drum, both walls of which are perforatedand mounted slidably in 'rela- 'rator orpre-centrifuge has the general reftion to each other in aXialdirect-ion.

F1gr3 shows another embod ment of a centrifugal separator provided with a double Walled drum, the inner wall being liquid penetrable the outer being unpenetrable.

According to Figs. 1a and 1b the first sepaerence'1,.and it is provided with-a drum having an impenetrable side wall 2, the second separator crsuper-centrifuge having the general referenceB, and is provided with a drum having a liquid penetrable side wall 4. The

penetrability-of the-last mentioned wall can be effected in many different ways, such as said wall.

When used'in practice, the set of machines described above functions in such a way that the liquid-containing material is at first fed into the pre-centrifuge (Fig. 1a) by means of the charging hopper 5 and the chute 6, suitable proportions being introduced into the drum for each charge; The liquidconstituent collecting towards .the centre of: the'm'a-. chine departs b'y means of the outlets? and by strainer plates or filters of suitable kinds.

- 55 A porousmaterial'may also be used for the the annular and stationary collector 8 provided with the outlet 8*. The layer of comparatively dry substance settled against the impenetrable drum jacket 2 is scraped off and down into the hopper 9 belonging to the super-centrifuge (Fig. 16). From the last mentioned hopper the substance by means of the screw conveyor 10 is fed into the drum belonging to the super-centrifuge and formed by the liquid penetrable jacket 4. In 1;- this second machinethe rest of water is removed and departsthrough the said jacket 4 into the non-rotating collector 11 surrounding the same, as thereafter todepart from the collector by means of the outlet 12.The final dry product is scraped out from the super-centrifuge on the inclined surface 13, from where it can be removed by any suitable means for further treatment, i. e. for final drying-by heat treatment within a suitable kiln. V I

The combined "first-and second stage machinediagrammatically shown in Fig. 2 comprises a separatordrum having the general reference 14. This drum. consists of double walls 15 and 16 which are both liquid penetrable, i. e. for instance perforated, such drum walls being constructed in such a manher that the outer one 16 may be displaced in axial direction in relation to the other. Hereby the combined'drum may naturally be made liquid penetrable ortnon-penetrable according to will, and when the perforations in the walls. 15 and 16 are in register the liquid may escape ,therethrough, but otherwise such escape is impossible.

According to this embodiment the liquid containing material is 'fedin by the inter-- mediary-of the hopper l7 and the chute 18,

andin the first stage of treatment the drum walls 15 and 16 are slid into such a position in relation to each other that the drum Wall is impenetrable; Thereby the liquid collected towards thecentre of'the drum is discharged through the outlets 19 and the annular collector 20 provided with the outlet 20*. During the second stage of treatment, 7 the outer drum wall 16 is displaced in. relation to the inner wall 15so that the perforationsare more or less in register. Then the 1-15 rest of the liquid will be thrown out through the penetrable drum wall, and the liquid thus escaping may be collected and led off in any suitable manner, forinstance as shown and described with reference to Fig. 1?).

l According to Fig. 3 the centrifugal machine, having the general reference 21, is provided with a drum built up'from an .inner liquidpenetrable wall 23 and an outer nonpenetrable wall 22, both of such walls being positioned in a little distance from each other rigidly connected-Otherwise this constructionis substantially the same as shown in Fig. 2. .7 i v This machine is also intended to act, as

single machine for a complete treatment, and during thefirst stage of separation the solid product collecting between the walls 22 and 23, when acted upon by'the interior pressure,

will slowly slide towards the open (left) end of the drum, which is somewhat restricted as shown in the drawing, and at this point the collected and compressed solid product, during the second stage of separation, will serve as a filter and liquid penetrable means for the rest of the liquid at hand in the substance remaining within the inner compartment of the drum.

The perforation of the inner drum acket 23 may be performed by means of annular openings, and the outer drum may be subdivided into a number of annular sections between which the liquid can escape after having passed the layer of peat at hand between the drum jackets.

Another method for removalof the peat mass from the machines described is by mounting the drum proper in a disconnectable manner on a supporting disc, so that the drum, after finishing the treatment, may be disconnected and turned upside down for the purpose of emptying. The interlocking means between the drum and the disc may be carried out in any suitable way. 7

According to the drawing the machines in all embodiments are supposed to have horizontal axis of rotation, but naturally the function will be substantially the same even if the axis is vertical or positioned in any inclination. The means for imparting a rotation to the drum may be constructed in any suitable manner independent of the invention, and the belt pulleys shown in the drawing are to be considered as an example only.

What I claim and desire to secure by Let V ters Patent is 1. A method for improving peat or other inferior fuels, and for transforming them into similar products of superior quality comprising first subjecting the material to wet-carbonization by heat treatment, thereafter removing the main contents of water i by centrifugation in a centrifugal machine having drum walls impenetrable to water, then subjecting the mass pre-dried by the first centrifugation to a second centrifugation in a centrifugal machine having drum water so that the solids are thrown out from r walls penetrable to water, and finally heating the mass resulting from the second stage of centrifugation for final drying 2. A method for improving peat or other inferior fuels, and for transforming them into similar products of superior quality comprising first subjecting the material to wet-carbonization by heat treatment, thereafter dehydrating the wet-carbonized material by means of centrifugal separation in two stages succeeding each other, the first of such stages being a centrifugation of the mass against drum surfaces unpenetrable to 

